The ants: a strategy of population concentration
A. N. Severtsov Institute of Ecology and Evolution, RAS
119071 Moscow, Leninsky pr., 33
e-mail: ferda@hk.ru
Ants are provided with a balanced system of reactions either to the original paucity of socia or to their secondary depopulation. This system can be defined as a strategy of population concentration. Both a successful reproduction of workers and queen fertilization are necessary conditions for ant communities' survival and development. Thus, the anthills must be large enough to ensure optimal conditions for reproduction. It is the strategy of population concentration that is directed to an accelerated attainment (or rehabilitation) by a socium of a stale of stable development by way of concentrating the existent ant staff in an accessible number of viable nests. This strategy is realized throughout the life of ant communities by way of (a) fusing the starting family cells left by founder females, (b) fusing small anthills during artificial ant migrations, (c) uniting smaller socia or their joining other anthills, (d) reintegrating the secondary anthills (fragmentants) after an exogenous fragmentation of formicaries. Pooling and the attraction of deficient demographic resources from outside form the most efficient and quickest ways of reaching or restoring the threshold density levels. By realizing this strategy, the ants solve their paramount problems of anthill or settlement conservation at any particular time, as well as of providing some prospects for ant existence in the future. These problems are so vital for ant socia that they appear to hold priority over such other characteristics of utmost importance as genetic kinship or even species identity. The priority of social basics over genetic ones is unequivocally supported through mixed formicaries. A necessary condition for the realization of the strategy of population concentration is tolerance of highly developed social systems to the diversity of forms and to deviations from the norm. The use of one and the same mechanism at all stages of the life both of an individual socium and large ant settlements is evidence of the universality of this strategy, as well as of its unconditioned importance to the life of ant communities.
